# 1.33 To perform mental calculations

 Page 1 / 1

## Memorandum

1.1 15

1.2 33

1.3 93

1.4 995

1.5 9 997

1.6 99 995

1.7 130

1.8 3 650

1.9 53

1.10 612 $\frac{1}{2}$

1.11 123

1.12 12

1.13 19

1.14 6

1.15 $\frac{1}{2}$

Puzzle out old code

1 286 1 335

- 539 - 934

1. 101

## Activity: to perform mental calculations [lo 1.9.1]

1. During the previous activities you have worked with very large numbers. It is equally important to be able to subtract small numbers correctly. Let us see how you will manage the following mental calculations test! Work as quickly and accurately as possible:

1.1 31 – 16 = ______________________________________________________

1.2 52 – 19 =______________________________________________________

1.3 101 – 8 =______________________________________________________

1.4 1 004 – 9 =______________________________________________________

1.5 10 003 – 6 =_____________________________________________________

1.6 100 002 – 7 =____________________________________________________

1.7 240 – 50 – 60 =__________________________________________________

1.8 4 000 – 350 =____________________________________________________

1.9 (530 × 10) ÷ 100 =________________________________________________

1.10 Halve 1 225: ____________________________________________________

1.11 Triple: ________________________________________________________

1.12 (11 × 12) - ______________________________ = 120

1.13 100 – (9 × 9) =___________________________________________________

1.14 (38 -___________________________________) ÷ 4 = 8

1.15 ____________________________________ × 850 = 425

15

Colour in: This time I have done GOOD AVERAGE POOR.

## Decipher the code!

Each letter represents a digit. Can you discover the numbers?

 ROAD _______________ DEEP _______________ - HIS _______________ - HER _______________ EWE _______________ ROD _______________

Do you know that this kind of mathematics is called Alpha-mathematics?

## Assessment

Learning Outcome 1: The learner will be able to recognise, describe and represent numbers and their relationships, and to count, estimate, calculate and check with competence and confidence in solving problems.

Assessment Standard 1.9: We know this when the learner performs mental calculations involving:

An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years? Kala Reply lim x to infinity e^1-e^-1/log(1+x) given eccentricity and a point find the equiation Moses Reply 12, 17, 22.... 25th term Alexandra Reply 12, 17, 22.... 25th term Akash College algebra is really hard? Shirleen Reply Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table. Carole find the 15th term of the geometric sequince whose first is 18 and last term of 387 Jerwin Reply I know this work salma The given of f(x=x-2. then what is the value of this f(3) 5f(x+1) virgelyn Reply hmm well what is the answer Abhi how do they get the third part x = (32)5/4 kinnecy Reply can someone help me with some logarithmic and exponential equations. Jeffrey Reply sure. what is your question? ninjadapaul 20/(×-6^2) Salomon okay, so you have 6 raised to the power of 2. what is that part of your answer ninjadapaul I don't understand what the A with approx sign and the boxed x mean ninjadapaul it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared Salomon I'm not sure why it wrote it the other way Salomon I got X =-6 Salomon ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6 ninjadapaul oops. ignore that. ninjadapaul so you not have an equal sign anywhere in the original equation? ninjadapaul hmm Abhi is it a question of log Abhi 🤔. Abhi I rally confuse this number And equations too I need exactly help salma But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends salma Commplementary angles Idrissa Reply hello Sherica im all ears I need to learn Sherica right! what he said ⤴⤴⤴ Tamia hii Uday hi salma what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks. Kevin Reply a perfect square v²+2v+_ Dearan Reply kkk nice Abdirahman Reply algebra 2 Inequalities:If equation 2 = 0 it is an open set? Kim Reply or infinite solutions? Kim The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined. Al y=10× Embra Reply Jeannette has$5 and \$10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
What is the expressiin for seven less than four times the number of nickels
How do i figure this problem out.
how do you translate this in Algebraic Expressions
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Got questions? Join the online conversation and get instant answers!