$MathMaster logo$

MathMaster

Home
general
4x21 using doubling twice strategy

Question

4x21 using doubling twice strategy

50

likes

250 views

Answer to a math question 4x21 using doubling twice strategy

$Expert avatar$

4.9

87 Answers

1. First doubling:

4 \times 21 = (2 \times 21) \times 2

2. Simplify inside the parentheses:

2 \times 21 = 42

3. Second doubling:

42 \times 2 = 84

Answer:

4 \times 21 = 84

Frequently asked questions (FAQs)

Math Question: Find the limit of (x^2 - 9)/(x - 3) as x approaches 3 using L'Hospital's Rule.

+

What is the range of the following data set: 12, 15, 18, 20, 22

+

What is the length of the side opposite to angle A in a triangle with angle A = 30°, side b = 5, and side c = 8?

+

New questions in Mathematics

Two fire lookouts are 12.5 km apart on a north-south line. The northern fire lookout sights a fire 20° south of East at the same time as the southern fire lookout spots it at 60° East of North. How far is the fire from the Southern lookout? Round your answer to the nearest tenth of a kilometer

reduction method 2x-y=13 x+y=-1

431414-1*(11111-1)-4*(5*3)

Imagine that you are in an electronics store and you want to calculate the final price of a product after applying a discount. The product you are interested in has an original price of $1000 MN, but, for today, the store offers a 25% discount on all its products. Develop an algorithm that allows you to calculate the final price you will pay, but first point out the elements.

A food delivery company charges on average a delivery fee of $5 per order (including food and shipping) and has monthly fixed costs of $600. If the average cost of each meal delivered that is revenue for the company is $10 and the company has a monthly profit of $800, how many orders must they deliver per month?

The profit G of the company CHUNCHES SA is given by G(x) = 3×(40 – ×), where × is the quantity of items sold. Find the maximum profit.

4.2x10^_6 convert to standard notation

The sum of two numbers is 6, and the sum of their squares is 28. Find these numbers exactly

Sean must chose a 6- digit PIN number for his online banking account.Each digit can be chosen from 0 to 9. How many different possible PIN numbers can sean chose.

There are 162 students enrolled in the basic mathematics course. If the number of women is 8 times the number of men, how many women are there in the basic mathematics course?

4. Show that if n is any integer, then n^2 3n 5 is an odd integer

By direct proof, how can you prove that “The sum of any three consecutive even integers is always a multiple of 6”.

Suppose the Golf ball market is perfectly competitive and the functions are known: Q = 120 – 2Px – 2Py 0.2I Q = 2Px 40 Where I = Consumers' income ($200) and Py = Price of Good Y (40) Calculate the equilibrium elasticity: a) 1.6 b) -6 c) 6 d) 0.6

What is the appropriate measurement for the weight of an African elephant?

using the math and science known about the jefferson river bridge Find a truss in use and develop a load diagram. Use a load of 50 lb on each joint along the bottom of the truss for a truss that actrs as a bridge and along the top joints for a truss that acts as a roof

If a|-7 and a|9, then a|-63

Determine the kinetic energy of a baseball whose mass is 100 grams and has a speed of 30 m/s.

Let G be the center of gravity of triangle ABC. We draw through A a parallel to BC on which we take a point D so that DG⊥BG. If the area of the quadrilateral AGBD is equal to s, show that AC·BD≥2·s.

An export company grants a bonus of $100,000 pesos to distribute among three of its best employees, so that the first receives double the second and the latter receives triple the third. How much did each person receive?

In an experiment to assess the effect of listening to audiobooks while driving, participants were asked to drive down a straight road in a driving simulator. The accompanying data on time (in milliseconds) to react when a pedestrian walked into the street for 10 drivers listening to an audiobook are consistent with summary statistics and graphs that appeared in the paper "Good Distractions: Testing the Effect of Listening to an Audiobook on Driving Performance in Simple and Complex Road Environments."† (Round your answers to four decimal places.) 1,018 1,007 1,054 988 937 1,030 1,065 1,011 860 1,106 A button hyperlink to the SALT program that reads: Use SALT. Calculate the variance for this data set. 7437.7333 Incorrect: Your answer is incorrect. Calculate the standard deviation for this data set. 86.2022 Incorrect: Your answer is incorrect.